Linked Life Data

1282950

Source:http://linkedlifedata.com/resource/pubmed/id/1282950

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
1993-2-12
pubmed:abstractText
The nitric oxide (NO) synthase activity present in murine J774.2 monocyte/macrophages was characterized in terms of its intracellular localization, substrate specificity, and Ca2+ dependency. Traces of constitutive NO synthase activity were found in the microsomal fraction from noninduced J774.2 cells, whereas no NO synthase activity was detected in the cytosol. After 24 h in the presence of bacterial lipopolysaccharide and mouse interferon, NO synthase activity was substantially increased in both fractions with 51-60% of the total activity present in the cytosol. These activities, however, were clearly different, for the microsomal enzyme was Ca2+ dependent, whereas the cytosolic NO synthase was not. Moreover, NG-hydroxy-L-arginine (L-HOArg), L-homo-arginine, and several L-arginine (L-Arg)-containing dipeptides could replace L-Arg as substrates for the Ca(2+)-independent NO synthase, whereas the Ca(2+)-dependent enzyme accepted only L-Arg, L-HOArg, or L-Arg-L-Arg as substrates. Thus, a microsomal Ca(2+)-dependent NO synthase is induced in J774.2 monocyte/macrophages with a substrate specificity different from the inducible Ca(2+)-independent NO synthase as well as the constitutive NO synthase in, for example, endothelial cells. Irrespective of their intracellular localization, therefore, at least three isoforms of NO synthase exist, all of which can accommodate substrates different from L-Arg in size, charge, and hydrophobicity.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0160-2446
pubmed:author
pubmed:issnType
Print
pubmed:volume
20 Suppl 12
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
S139-41
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Characterization of a microsomal calcium-dependent nitric oxide synthase in activated J774.2 monocyte/macrophages.
pubmed:affiliation
William Harvey Research Institute, St. Bartholomew's Hospital Medical College, London, England.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't